Automatic information reading system using photoluminescent detection means

ABSTRACT

A process for encoding data and apparatus for recording and retrieving the same. The encoding is accomplished by depositing, on an area for each datum of said data, a first plurality of binarily-weighted ink components, whose presence or absence defines the significant value of a digit, and a second plurality of binarily-weighted ink components, whose presence or absence defines the order of the digit. The inks used photoluminesce in distinct narrow wavebands when subjected to ultraviolet radiation. The apparatus for retrieving the data includes a source of ultraviolet radiation for periodically illuminating a scanning zone to where the data to be read is moved. A scanning device is used to scan the scanning zone during the period when the ultraviolet radiation is on, so as to detect the fluoresence of those ink components which are present. Each datum may also be so shaped as to be human-readable. An optical system is used to direct the detected fluoresence to an array of light-responsive members. Each member of the array is responsive to the fluorescence of only one ink component, thereby registering the presence or absence of that particular ink component in the data. Successive passes by the scanning device repeatedly scan the data, which may be randomly oriented relative to the scanning zone. Conventional logic circuitry may be used to interpret the output of the array of light-responsive members.

I United States Patent Trimble [451 May 30, 1972 [72] lnventor: Cebern B. Trlmble, Dayton, Ohio [73] Assignee: The National Cash Register Company,

Dayton, Ohio [22] Filed: Sept. 29, 1970 [21] Appl. No.: 76,493

[52] US. Cl. ..250/71 R, 235/6l.l l, 250/7l.5 R,

Primary ExaminerMorton J. Frome Attorney-Louis A. Kline, Albert L. Sessler, Jr. and Elmer Wargo [57] ABSTRACT A process for encoding data and apparatus for recording and retrieving the same. The encoding is accomplished by depositing, on an area for each datum of said data, a first plurality of binarily-weighted ink components, whose presence or absence defines the significant value of a digit, and a second plurality of binarily-weighted ink components, whose presence or absence defines the order of the digit. The inks used photolu- -minesce in distinct narrow wavebands when subjected to ultraviolet radiation. The apparatus for retrieving the data includes a source of ultraviolet radiation for periodically illuminating a scanning zone to where the data to be read is moved. A scanning device is used to scan the scanning zone during the period when the ultraviolet radiation is on, so as to detect the fluoresence of those ink components which are present. Each datum may also be so shaped as to be humanreadable. An optical system is used to direct the detected fluoresence to an array of light-responsive members. Each member of the array is responsive to the fluorescence of only one ink component, thereby registering the presence or absence of that particular ink component in the data. Successive passes by the scanning device repeatedly scan the data, which may be randomly oriented relative to the scanning zone. Conventional logic circuitry may be used to interpret the output of the array of light-responsive members.

5 Claims, 7 Drawing figures Patented May 30, 1972 3,666,946

6 Shoots-Shed 1 INVENTOR CEBURN B. TRIMBLE BY WM :Mfc)

HIS ATTORNEYS Patented May 30, 1972 3,666,946

6 Sheets-Sheet 3 DATA FIG. 4 97 RESET 76 RECOGNITION 1' 54a 70) MERCHANDISE TRANSPORT G PRESENCE CONTROL E A MEMORY aALARM HOUSE LIGHT L 82 PACKAGE REFLECT|0N MERCHANDBE I) ABSENCE 84 86 92 TO CONTROL GATE I34 93 BLOCK M Q CONTROL lOO vw A LEVEL J INVENTOR CEBERN B. TRIMBLE HIS ATTORN Patented May 30, 1972 3,666,946

6 Sheets-Sheet 4 otrvcd INVENTOR CEBURN B. TRIMBLE ms ATTORNEYS ma WM Patented May 30, 1972 3,666,946

6 Shoots-Sheet 5 INVENTOR CEBURN B. TRIMB LE Mm 4 Z96 BY M HIS ATTORNEYS Patented May 30, 1972 3,666,946

6 Sheets-Sheet 6 ,HG )E FIG.7

L 3 X h INVENTOR CEBERN B. TRIMBLE 31; QKg

BY MM 'ms ATTORNE AUTOMATIC INFORMATION READING SYSTEM USING PHOTOLUMINESCENT DETECTION MEANS BACKGROUND OF THE INVENTION so as to code the data for automatic or semi-automatic reading thereof.

One of the'problems encountered with optical codes which use a large number of colors, or colorants," is that it is difficult to distinguish one color from another with consistent accuracy. This problem was partially, solved through the use of coded inks in which at least some of the components contain chelated lanthanide ions, which, under ultraviolet light, luminesce in very narrow bands because the chelated ions are excited by the ultraviolet light to a particular metastable state, and, in falling back to a lower energy level, emit radiation of a narrow wavelength band, depending on the particular lanthanide ion used. Coding is generally accomplished by the presence or absence of the particular components, and this coding technique permits a number of symbols equal to 2" 1, where-n is the number of components. With four components, for example, the number of different symbols available for coding is 15. A discussion of these coded inks and variations in coding techniques may be found in the following U.S. patents: U.S. Pat. No. 3,340,982, which issued on Sept. 12, 1967, on the application of Robert E. Torley and Donald J. Berets; U.S. Pat. No. 3,492,660, which issued on Jan. 27, 1970, on the application of Frederick Halverson; and U.S. Pat. No. 3,500,047, which issued on Mar. 10, 1970, on the application of John William Berry.

In general, the prior-art codes are limited to a fixed number of different symbols obtainable through different combinations with a fixed number of coded inks. Because it is desirable to encode more information than merely the price of an article being sold, for example, it is necessary that the particular encoding technique used be adaptable to produce a large number of different symbols with a minimum number of coded inks.

The present invention enables a large number of different symbols to be encoded with'a minimum number of coded inks.

' In the prior-art encoding techniques, generally, seven coded inks will provide 127 different combinations according to the equation 2' l, where n is the number of different coded inks available. Under the present invention, seven coded inks, or colorants," will provide an encoded number" having up to eight numerical digits and symbols, which is a considerable increase in encoding capacity of the system. The apparatus for reading the encoded data can read the data even if it is partially damaged. Also, the encoded data may be combined with other inks to make the data human-readable as well as machine-readable.

SUMMARY OF TI-IE INVENTION This invention relates to a process for encoding data and to apparatus for recording and retrieving the same. The encoding isaccomplished by depositing, on an area for each datum of the said data, a first plurality of binarily weighted ink components, or colorants, whose presence or absence defines the significant value of the digit. A second plurality of binarily weighted ink components, or colorants, whose presence or absence defines the order of the digit, is then deposited next to or mixed with the first plurality. The inks used photoluminesce in distinct narrow wavebands when subjected to ultraviolet radiation. The apparatus for reading the encoded data includes an ultraviolet illuminating means for periodically illuminating a scanning zone to which the encoded data to be read is moved. A scanning means is used to scan the data at the scanning zone, and the fluorescence from the coded inks present in the data is imaged to an array of light-responsive members by an imaging means. Each member of the array is responsive to only one light frequency emitted from the coded inks, so as to indicate the presence or absence of the corresponding ink. The particular light-responsive members which are energized represent that particular digit scanned. As other digits of the encoded data reach the scanning zone, they are similarly scanned. The individual digits scanned are then processed by logic circuitry to develop the entire encoded data.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic view, in perspective, of the reading apparatus of this invention, showing the ultraviolet illumina tion means, the scanning means and scanning zone, and imaging means for directing the light fiuorescing from the encoded data onto an array of light-responsive members.

FIG. 2 is a diagram showing how encoded data, eight digits long, is made up of first and second portions of binarilyweighted ink components.

FIG. 3 is a diagrammatic showing of a hand stamp, showing, in coordinate form, the ink components contained in each characteror digit to be encoded.

FIG. 4 is a general schematic diagram in block form showing a portion of the control means associated with the reading apparatus.

FIG. 5 is a schematic diagram of a matrix decoder tree circuit for obtaining an output representing the different ink components present and absent for the portion of the datum containing the significant digit.

FIG. 6 is a schematic diagram of a matrix decoder tree circuit for obtaining an output representing the different ink components present and absent for the portion of the datum containing the order of the significant digit.

FIG. 7 is a schematic diagram showing a capacitor storage memory matrix circuit which is used to store the data developed from the scanning operation.

DETAILED DESCRIPTION OF THE INVENTION FIG. 1 is a diagrammatic view, in perspective, of the reading apparatus ofthis invention, which is designated generally as 20 and is shown, for illustration, as being used in a check-out counter at a retail store, like a grocery store.

The general construction and operation of the apparatus 20 shown in FIG. 1 are as follows. Items to be purchased (like 22 and 24) are positioned on a conventional powerized conveyor belt means 26, so that coded data on each item is positioned upwardly, as shown. The items may be placed on the belt means 26 in a random orientation thereon; however, the items should be so spaced as to have the items moved generally in single file by the belt means 26 to a scanning zone 28.

While at the scanning zone (FIG. 1), the coded data (like 30) on the item 22 is periodically irradiated by ultraviolet light from an ultraviolet illumination means 32. As stated in the Summary, the coded inks, or colorants, used in the'coded data photoluminesce in distinct, narrow wavebands when subjected to ultraviolet light. The fluorescence from the coded inks is sampled by a conventional scanning means 34, which includes a rotating disc 36 with apertures 38 therein. As the disc 36 rotates, the apertures 38 sample a small portion of the coded data 30 at the scanning zone 28. A conventional clock generator means 40, working in cooperation with the apertures 38 of the disc 36, is used to provide a clocking signal for gized. During these times, those coded inks which are present.

in the coded data will fiuoresce, and their energy will be directed by a conventional optical imaging system (represented by lenses 42 and 44) to an array 46 of lightresponsive members. Naturally, any general illumination lights near the scanning zone 28 would have to be phased with the illumination means 32, so that no visible light is present during the data samplings at the scanning zone.

The array 46 (FIG. 1) has the following construction. The underside of the array (as viewed inFIG. 1) has a plurality of lenticular lenses 48 located in a planar support member 50. Fluorescence from the sampled coded inks present at the scanning zone 28 is directed to each of the lenticular lenses 48 by the-optical imaging system. Each lenticular lens 48 has associated therewith a light filter 52 and a photoelectric cell 54. The filter 52 is so selected as to enable the light energy from only one coded ink to pass therethrough to register upon the associated cell 54. In some instances, several light response peaks are associated with one ink; therefore the detection of such an ink may require the use of several cells 54. This aspect will be described in detail later herein. The filters 52 are mounted in an opaque mask-type support member 56, which is sandwiched between the support member 50 and an opaque support member 58, inwhich the photoelectric cells 54 are located. Each filter 52 and cell 54 are optically aligned with their associated lenticular lens 48. As each portion of the coded data is scanned, each coded ink present will energize the associated photoelectric cellor cells in the array 46. The particular combination of cells 54 which is energized will represent the coded data 30 which has been sampled. Succes sive scans by the disc 36, coupled with an advancement of the item 22 past the scanning zorie, will complete the scanning of the entire coded data 30. The output of the array of photoelectric cells is processed by the control means, to be later described.

Before proceeding further, it appears appropriate to discuss the coded inks used and the method of encoding the data. The United States patents cited "earlier in this specification adequately describe the various coded inks which may be used. The coded inks include a mixture of photoluminescent materials along with ordinary color inks which may be used to make the coded data human-readable as well as machinereadable. The coded data may be printed directly on the items where no confusion with printed matter on the item exists, or it may be printed on separate labels which are affixed to the item, as is customarily done.

The photoluminescent materials for the coded inks include a chelate of lanthanide ion. Usually, these materials are almost colorless; however, under ultraviolet light, they fluoresce in narrow wavelength bands. In addition, other materials which are activated with trivalent rare earths may be included in the ink coding information system; an example of such a substance is europium activated gadolinium oxide. These coded ink materials differ considerably from most other fluorescent substances, whose fluorescence spectrums usually consist of broad bands. These inks photoluminesce in sufficiently narrow bands so as to make individual detection thereof feasible. Some of the inks have several prominent response peaks; however, the bands of the response peaks are sufficiently narrow to permit detection. For additional examples, the coded inks used may be chelates of europium, terbium, and samarium.

FIGS. 2 and 3 show the specific encoding used in this invention. In the example used to illustrate this invention, seven different coded inks are used to obtain eight significant digits of coding. Each datum of the coded data is composed of up to seven different coded inks, with four different coded inks being used for the first portion of the datum and three different coded inks being used for the second portion of the datum. The first portion of the datum is used to denote the significant number; i. e., whether it is a 1, 2, 9, etc., or a character like A or B. The second portion is used to encode the order of the particular significant number; i. e., whether it is in units place, 's place, etc. For the first portion of the datum, four difierent inks of the type described are lettered a, b, c, and d and are binarily weighted, as shown under the bracket marked A." For example, the significant digit "I would have only the coded ink marked a" in the first portion of the datum, as shown in FIG. 3. For the second portion of the datum, three different inks of the type described are lettered e, f, and g, and are binarily weighted as shown within the bracket marked n" in FIG. 3. For example, the significant digit 1," when denoting unit's place, would have none of inks e, f, or g present. For the significant digit l to denote 10's place, only ink 2 would have to be present in the second portion. For the significant character "A (located in the box marked 60 in FIG. 3), all seven inks a, b, c, d, e,f, and 3 would be necessary to identify the character. How a whole number like 84,729,729 is composed of the various coded inks is shown in FIG. 2.

The composition of the coded inks for numbers and characters is shown in FIG. 3, which represents the printing bands of a conventional hand stamp which may be used to stamp theparticular data desired on an item. Each box like 60 in FIG. 3 represents a segment of a band of a hand stamp. Naturally, each segment of the hand stamp is separated from adjacent segments by a conventional ink-impervious barrier, so as to prevent bleeding of inks from one segment to another. Each segment for each character has, included in it, all of the special inks a, b, c, d, e, f, and g which are necessary for coding that particular character. The special inks may be deposited in each segment, which is made of porous rubber to retain the inks. Conventional porous rubber hand stamps may be used. The special inks are mixed prior to being deposited in the appropriate segment of the band, so that each portion of the character to be printed has a mixture of all the coded inks present for that character. If the data is to be human-readable also, a compatible coloring agent may be included in the mixture.

Because each portion of the character to be printed contains a mixture of all the coded inksnecessary to produce that character, the sampling or reading process is simplified. For example, as the item 22 (FIG. 1 proceeds towards the scanning zone, the first portion of the coded data 30 to reach the scanning zone will be a portion of the number4." Several passes of the scanning means 34 will sample portions of the "4" prior to the number 3" of the coded data 30 being scanned. Each portion of the 4" which is scanned contains all the inks necessary to identify it as to significant character and positional weight. A useful analogy for understanding this concept is that each sample scanned is like a molecule in that it contains all the identifying characteristics of the chemical substance to which it relates. It is not necessary that all the inks making up a number be shaped like a 4," for example, to be machine-readable; shaping the mixture of inks in the form of a human-readable 4 'is done merely to also make the 4'? human-readable. The successive samplings of the 4" will be routed to processing circuitry which will identify the inks sampled as being a 4 located in units place, as represented by the box numbered 62 in FIG. 3, which shows the composition of this number to contain only ink c. As the number 3" of coded data 30 reaches the scanning zone 28, a portion of the 3 will be scanned, followed by a portion of the 4 also being scanned. The sampling of the "3 is routed to the processing circuitry, to be later described, which will identify the inks sampled as being a 3 located in l0s place, as represented by the box numbered 64 in FIG. 3. A character is continually sampled at the scanning zone until it is moved beyond the scanning zone 28 by the belt means 26. The individual samplings of each character are routed to the processing circuitry, where they are identified as generally described. When the item 22 is moved by the belt means 26 to a position downstream of the scanning zone, a read-out signal is generated by the item 22 leaving the scanning zone 28, which read-out signal causes the processing circuitry to total the individual samplings taken and provide a read-out, and also resets the processing circuitry to accept data from the next following item 24 in F IG. 3. The items like 22 and 24 may be located anywhere on the belt means 26 as long as the coded data is facing up and the items are sufficiently spaced along the direction of travel past the scanning zone 28 so that only one item is read at a time. The specific speed of the belt means 26 can beso chosen as to provide a sufiiciently fast transport rate (like 1 inch per second) for items carried thereby. The scan rate may beabout 3,600 scans per minute for characters having a height of approximately one fourth of an inch.

Part of the processing circuitry alluded to earlier is shown in FIG. 4. Because individual components of the circuitry may be conventional, they are shown here only in block form. As stated earlier, general illumination lights, like the lamp 66 in FIG. 1, are phased with the ultraviolet illumination means 32 having an ultraviolet lamp 68, so that no visible light is present during selected ones of the scan sweeps over the scanning zone 28. The clock generator means 40, shown in FIGS. 1 and 4, is conventionally used to synchronize the scanning and to provide timing and control signals for the processing circuitry. The general illumination lamp 66 and the ultraviolet lamp 68 are conventionally driven from a 60-cycle alternating current source, so that, when the lamp 66 is on, the lamp 68 is off, and vice versa. When the general illumination lamp 66 is on, one of the apertures 38 of the disc 36 scans the scanning zone 28, enabling one of the photoelectric cells, like 54a, to be used to detect the presence or absence of an item like 22 (FIG. 1) at the scanning zone through the use of visible light. The cell 54a selected for determining the presence or absence of reflected visible light from the item 22 would have the appropriate filter 52 in front of it to screen out any ultraviolet light and to permit only visible reflected light from an item 22 to reach the cell 540. The belt means 26 is black in color to eliminate unwanted reflections. The output from the cell 54a (FIG. 4) is conventionally amplified in an amplifier 70, whose output is fed to a gate 72'. The clock generator means 40 controls the gate 72 so as to trigger a merchandise presence memory circuit 74 when the cell 54a is energized. After the circuit 74 is triggered, data like 30 (FIG. 1) must be detected before the item 22 is allowed to leave the exit area of the belt means 26. If no data is detected after the circuit 74 is triggered, a data recognition circuit 76 will trigger a transport control and alarm circuit 78, which will inhibit the movement of the belt means 26 and give an audio signal indicating to an operator that no data is present on an item to be read. The operator can then correct the problem or remove the item without data and reset the apparatus by a reset circuit 80. After an item, like 22 (FIG. 1), passes the scanning zone 28, a merchandise absence signal is generated by a merchandise absence circuit 82, and the signal is used to cause the processing circuitry to evaluate the samplings taken and to reset the processing circuitry, as will be described later.

The various coded inks present in the coded data 30 on an item (like 22) at the scanning zone 28 (FIG. 1) are detected by circuitry, part of which is shown in FIG. 4. As stated earlier, the lamps 66 and 68 (FIG. 1) are energized at different times, so that, when the general illumination lamp 66 is on, the ultraviolet lamp 68 is off, and vice versa. When the general illumination lamp 66 is on, one of the apertures 38 is used to scan the zone 28 to detect for the presence or absence of an item 22. The next following aperture 38 scans the zone 28 when the lamp 66 is deenergized and the ultraviolet lamp 68 is on. During this scan, those coded inks present in the coded data 30 will fluoresce and will be imaged onto the photoelectric cell array 46, as previously described. Each coded ink fluoresces at its own wavelength represented by A M, etc., to A, on FIG. 4 to energize its associated photoelectric cell 54. Some of the corresponding components for the different coded inks have been omitted from FIG. 4 to simplify the drawing. The output of each cell 54 is amplified and normalized by an associated amplifier 84, whose output is fed to an associated threshold gate 86. A threshold level 88 is fed into each of the gates 86. The output of each gate 86 is fed into an associated gate 90, which strips the analog information from the signal. As stated earlier, some of the inks have several prominent response peaks which are sufficiently narrow to permit detection. When such an ink is used, some extra gating means are necessary in the circuitry shown in FIG. 4, as, for example, the extra gating means shown in relation to the ink having response peaks in the wavelengths represented by A, and A The outputs from the gates 86 associated with the inks having wavelengths A, and A, are fed into an AND gate 91, whose output is fed into an associated gate 90, which strips the analog information from the signal. When both wavelengths A, and A, are present, the presence of ink 0 will be recorded at the associated amplifier 92. The output from a program control circuit 93 associated with the clock generator means 40 is also fed into each of the gates 90 to inhibit the output of the gates 90 during the times that visible light lamp 66 (FIG. 1) is energized. Only those outputs of the cells 54 which occur during those scan times when the ultraviolet lamp 68 is energized are permitted to pass through the gates 90. A photocell 95, associated with the ultraviolet lamp 68, is energized each time the lamp 68 is energized, and a photocell 97, associated with the general illumination lamp 66, is energized each time the lamp 66 is energized; these two photocells are part of the program control circuit 93. The output of each gate 90 is fed to an associated amplifier 92 and inverter 94. Each amplifier 92 develops an output signal at a logic level (like V,,) to represent the presence of the associated coded ink. The inverter 94 associated with each amplifier 92 develops the conjugate signal (like V,,') at the logic level to indicate the absence of the corresponding ink component. The outputs like V,,, V,,, etc., from each of the amplifiers 92 are fed into an OR circuit 96, whose output is fed to a gate 98. The output from a blocking oscillator is also fed to the gate 98. The oscillator 100 produces an output signal having a constant pulse width (representing a fixed time duration) which is utilized in a capacitor storage memory matrix shown in FIG. 7. The output of the gate 98 is amplified in an amplifier 102, whose output is utilized in the memory matrix shown in FIG. 7. This aspect will be described later.

The outputs from the amplifiers 92 and their associated inverters 94 are decoded through the use of conventional matrix decoder trees shown in FIGS. 5 and 6.

The outputs associated with the coded inks a, b, c, and d (which relate to the significant number encoded) are decoded by the matrix decoder tree shown in FIG. 5. The outputs V,, and V, coming from the associated amplifier 92 and inverter 94, respectively, and the similar outputs associated with inks b, c, and d are conventionally decoded by the matrix (FIG. 5) to produce the various outputs shown. For example: If only coded ink a is present for the significant number, an output would appear at the terminal marked a b c d in FIG. 5. This terminal represents the numeral l which is enclosed in a circle in FIG. 5. The assignment of characters in FIG. 5 corresponds to the coding arrangement shown in FIG. 3. As another example, if all the inks a, b, c, and d are present, an output would be recorded at the terminal marked a b c d in FIG. 5. This terminal represents the significant number" or character A which corresponds to row 15 in FIG. 3. The various outputs of the decoder tree in FIG. 5 are arbitrarily assigned to the row or Y axis of the memory matrix shown in FIG. 7.

The outputs associated with the coded inks e, f, and g (which relate to the particular order of the significant number encoded) are decoded by the conventional matrix decoder tree shown in FIG. 6. The outputs like V, and V,,' coming from the associated amplifier 92 and inverter 94, respectively, shown in FIG. 4, and the similar outputs associated with coded inks V and V,, are conventionally decoded by the matrix decoder tree shown in FIG. 6 to produce the various outputs shown therein. For example: If only coded ink 2" is present in the group of inks whose presence or absence determines the particular order of the significant digit, an output would appear at the terminal marked e f g in FIG. 6. This terminal represents the second order, or IOs place, and is also marked X(2), which is shown on FIG. 3. The various outputs of the decoder tree shown in FIG. 6 are arbitrarily assigned to column or X axes of the memory matrix shown in FIG. 7.

The outputs from the matrix decoder trees of FIGS. and 6 are connected to the capacitor storage memory matrix circuit designated generally as 104 in FIG. 7. The purpose of the matrix circuit 104 is generally to accumulate the data which is detected during successive scans by the apparatus shown in FIG. 1. As stated earlier, the row terminals like Y1, Y2 to Y16 refer to the significant digits shown in FIG. 3, and the column terminals like X(1), X(2) to X8 refer to the order of the particular significant digit.

The circuit 104 (FIG. 7) is generally made up of a plurality of similar subcircuits like 106, only one of which will be described in detail. The subcircuit 106 includes an AND gate 108, which has one input lead 110 connected to a common conductor 1 12, which is connected to the input terminal X( 1) from FIG. 6. The remaining input lead 114 of the gate 108 is connected to a common conductor 116, which is connected to the input terminal Y1 from FIG. 5. The output of the gate 108 is connected to one terminal of an associated capacitor 118, whose remaining terminal is connected to a common conductor 120. The output of the gate 108 is also connected to an associated conventional comparison circuit 122, whose output is connected to a conventional memory flip-flop circuit 124. The output of the gate 108 is also connected to one terminal of an isolation diode 125, whose remaining terminal is connected to a common conductor 126. The conductor 126 is connected to the input of a conventional threshold amplifier 128, whose output is connected to a common conductor 130, which is connected to another input of the comparison circuit 122. A signal to trigger the comparison circuit 122 is fed over a common conductor 132 from a control gate 134, which is triggered by the merchandise absence circuit 82, shown in FIG. 4.

Some additional details about the circuit 104 shown in FIG. 7 are as follows. Each AND gate (like 108) of the subcircuits is connected to a row conductor and a column conductor to obtain its inputs. For example, the. AND gate 136 of the subcircuit 138 (which is identical to the subcircuit 106, already described) has one input terminal connected to a row conductor 140 connected to the input terminal Y2 and the other input terminal connected to a column conductor which for this circuit is the conductor 1 12. One terminal of each of the capacitors like 142 is connected to a common conductor 146, and the capacitor 118 is connected to the conductor 120. The conductors I20 and 146 connect with another common conductor 148, so that one terminal of each of all the capacitors like 118, 142 is connected to the conductor 148, which is connected to the output of an operational amplifier 150. The amplifier 150.is of the type which goes to saturation in either direction and is maintained in an off direction by a conventional bias 152. The amplifier 150 is controlled by the output J of the amplifier 102 (FIG. 4), which in effect makes the amplifier 150 act as a switch, so that the charging of capacitors like 118 and 144 of FIG. 7 occurs only during the times when the fixed-width pulse from the oscillator 100 passes through the gate 98, shown in FIG. 4. An isolating diode 125 for each capacitor like 118 is connected to the associated AND gate (like 108) and the associated common conductor (like 126) to isolate the capacitors in the circuit 104 from one another.

The circuit 104 shown in FIG. 7 operates in the following manner. The outputs from the decoder trees of FIGS. 5 and 6 are fed into the corresponding input terminals of the circuit 104 of FIG. 7 to condition the appropriate AND gates like 108 and 136. Assume that the only coded ink present in the data being read is the one having a wavelengthk consequently, an output pulse will appear at the terminals Y2 and X(l). Under these conditions, the AND gate 136 will be conditioned, and the associated capacitor 142 will be charged for an interval controlled by the blocking oscillator 100, the gate 98, the power amplifier 102 (FIG. 4), and the amplifier 150 (FIG. 7). As successive scans are made by the scanning disc 36 (FIG. 1), the capacitor 142 will be successively charged to a higher voltage, assuming that only coded ink b is present. It is possible that some of the column capacitors like 118, which are associated with the conductor 112 (connected to the conductor 112 through their respective AND gates), may also be charged, due to errors in reading or errors in reading data which is partially damaged. However, because successive scans of the data are made, that particular capacitor which is charged the most will most likely represent the correct reading. Because the voltages passing through the isolating diodes like 154 to the conductor 126 may be different, the threshold amplifier 128 is set at about 75 percent of the highest voltage received on the conductor 126, and this value is fed into each of the comparison circuits 122 connected to the conductor 130. When the coded data is completely read (as signalled by the item 22 in FIG. 1 leaving the scanning zone 28), a signal from the control gate 134 (FIG. 7) will trigger all the comparison circuits 122. Each comparison circuit 122 will compare the voltage at its associated capacitor with the voltage coming from the associated threshold amplifier 128. In the example given, the capacitor 142 would have the highest voltage of the capacitors connected to the conductor 126, and, consequently, the flip-flop 156 of the subcircuit 138 would be accordingly set to indicate the presence of the character 2 in units place. The outputs from the flip-flops 124, 156 may be conventionally connected to a display device (not shown) or conventional processing circuitry, which may include a computer.

While this embodiment has been described as utilizing the fluorescent characteristics of the inks, their phosphorescent characteristics may also be used; however, there appear to be more noise problems when the phosphorescent characteristics are used.

What is claimed is:

1. The process for the coding and retrieval of data comprising the steps of:

a. depositing, on an area for each datum of said data, a first plurality of binarily weighted ink components whose presence or absence defines the significant value of a digit;

b. depositing on said area, for each datum of said data, a second plurality of binarily weighted ink components whose presence or absence defines the order of the digit;

0. moving said area with the data thereon to a scanning zone;

d. periodically illuminating said scanning zone with ultraviolet radiation;

e. scanning a portion of the data at said zone so as to detect the photoluminescence of the ink components present in the portion of the data scanned;

. imaging the photoluminescence of the ink components present onto each member of an array of light-responsive members in which each of the light-responsive members is responsive to the photoluminescence of only one ink component to thereby produce a signal to indicate the presence of the corresponding ink component in the portion of the data scanned;

g. decoding said signals in a first decoder matrix to produce a first signal representative of the significant value of the digit being scanned;

h. decoding said signals in a second decoder matrix to produce a second signal representative of the particular order of the digit being scanned; and

i. storing said first and second signals for each digit being scanned to produce a resulting signal indicative of the significant value and particular order of the digit being scanned upon the occurrence of a readout signal.

2. The process as claimed in claim 1 in which the steps of depositing said first and second pluralities of ink components are combined in one depositing step with said first and second pluralities of ink components being mixed together prior to the one depositing step; and in which said depositing step is effected by a hand stamp with said one depositing step shaping said first and second pluralities of ink components into a human-readable character.

3. An apparatus for reading digits of data recorded in a plurality of inks in which each ink photoluminesces at a particular discrete waveband when illuminated with ultraviolet light, comprising:

a scanning zone; means for moving said data to said scanning zone; illuminating means for periodically illuminating said data with ultraviolet light at saidscanning zone; an array having a plurality of light-responsive members adapted to produce a signal when energized, each of said members being responsive to the waveband of only one of said links during photoluminescence; scanning means for periodically scanning a small part of each digit of said data at said scanning zone as said data is moved thereto; imaging means for imaging the photoluminescence of the data scanned onto each of said members so that the particular members energized or not energized are indicative of the inks present or not present in said data, and each of those members energized producing a corresponding signal; a first decoder matrix .to decode said signals into a first signal representative of the significant value of the digit being scanned; I a second decoder matrixfto decode said signals into a second signal representative of the particular order of the digit being scanned; a memory matrix means to combine said first and second signals to produce a resulting signal representative of the digit being scanned and to store said resulting signals of all the data scanned until a readout signal is obtained, said matrix means comprising:

row input terminals to receive the first signals from said first decoders matrix;

column input terminals to receive the second signals from said second decoder matrix;

a storage means for each row input terminal and column input terminal; I

a gate means for each storage means to energize the associated storage means upon the simultaneous occurrence of a first signal and a second signal from the associated row and column input terminals to produce said resulting signal representative of the digit being scanned; and

readout means to receive the outputs of said gate means upon the occurrence of said readout signal and thereby record the presence of the digits being read.

4. The apparatus as claimed in claim 3 in which said scanning means and imaging means are cycled so that the inks are scanned during intervals in which the ultraviolet light is on, so that the inks present will be detected by their fluorescence and in which said illuminating means also includes a source of visible light for periodically illuminating said scanning zone;

said array including a light-responsive member which is responsive to visible light,

said data being located on an item adapted to reflect visible light,

said scanning means being adapted to scan said item during the interval in which it is illuminated with visible light at said scanning zone and thereby energize the associated light-responsive member to enable said readout means;

said readout signal being produced when said item leaves said scanning zone; and

said storage means including capacitor means.

5. In combination, coded data, and a reading apparatus therefor;

each datum of said data comprising:

a first portion containing a plurality of binarily weighted ink components whose presence or absence defines the significant value of a digit; and

a second portion containing a plurality of binarily weighted ink components whose presence or absence defines the particular order of the digit;

each said ink component emitting a different specific light frequency when irradiated by ultraviolet light;

said apparatus comprising:

ultraviolet illununation means for periodically illuminating with ultraviolet light a scanning zone which said data passes;

scanning means for scanning a small portion of each datum at said scanning zone;

an array of light-responsive means having members, with each one thereof being responsive to only one light frequency emitted from said coded inks so as to indicate the presence or absence of the corresponding ink, thereby defining said datum;

imaging means for imaging the light emitted from said inks to each of said light-responsive members of said array, with each of said members which is energized producing a corresponding signal;

a first decoder matrix to decode said signals into a first signal representative of the significant value of the datum being scanned;

a second decodermatrix to decode said signals into a second signal representative of the particular order of the datum being scanned; and

a memory matrix comprising:

row input terminals to receive said first signals and column input terminals to receive said second signals;

a storage means for each row input terminal and column input terminal;

a gate means for each storage means to energize the associated storage means upon the simultaneous occurrence of a first signal and a second signal from the associated row and column input terminals; and

readout means for each said storage means to receive the output from the associated storage means upon the occurrence of a readout signal and thereby record the presence of the data scanned. 

1. The process for the coding and retrieval of data comprising the steps of: a. depositing, on an area for each datum of said data, a first plurality of binarily weighted ink components whose presence or absence defines the significant value of a digit; b. depositing on said area, for each datum of said data, a second plurality of binarily weighted ink components whose presence or absence defines the order of the digit; c. moving said area with the data thereon to a scanning zone; d. periodically illuminating said scanning zone with ultraviolet radiation; e. scanning a portion of the data at said zone so as to detect the photoluminescence of the ink components present in the portion of the data scanned; f. imaging the photoluminescence of the ink components present onto each member of an array of light-responsive members in which each of the light-responsive members is responsive to the photoluminescence of only one ink component to thereby produce a signal to indicate the presence of the corresponding ink component in the portion of the data scanned; g. decoding said signals in a first decoder matrix to produce a first signal representative of the significant value of The digit being scanned; h. decoding said signals in a second decoder matrix to produce a second signal representative of the particular order of the digit being scanned; and i. storing said first and second signals for each digit being scanned to produce a resulting signal indicative of the significant value and particular order of the digit being scanned upon the occurrence of a readout signal.
 2. The process as claimed in claim 1 in which the steps of depositing said first and second pluralities of ink components are combined in one depositing step with said first and second pluralities of ink components being mixed together prior to the one depositing step; and in which said depositing step is effected by a hand stamp with said one depositing step shaping said first and second pluralities of ink components into a human-readable character.
 3. An apparatus for reading digits of data recorded in a plurality of inks in which each ink photoluminesces at a particular discrete waveband when illuminated with ultraviolet light, comprising: a scanning zone; means for moving said data to said scanning zone; illuminating means for periodically illuminating said data with ultraviolet light at said scanning zone; an array having a plurality of light-responsive members adapted to produce a signal when energized, each of said members being responsive to the waveband of only one of said links during photoluminescence; scanning means for periodically scanning a small part of each digit of said data at said scanning zone as said data is moved thereto; imaging means for imaging the photoluminescence of the data scanned onto each of said members so that the particular members energized or not energized are indicative of the inks present or not present in said data, and each of those members energized producing a corresponding signal; a first decoder matrix to decode said signals into a first signal representative of the significant value of the digit being scanned; a second decoder matrix to decode said signals into a second signal representative of the particular order of the digit being scanned; a memory matrix means to combine said first and second signals to produce a resulting signal representative of the digit being scanned and to store said resulting signals of all the data scanned until a readout signal is obtained, said matrix means comprising: row input terminals to receive the first signals from said first decoder''s matrix; column input terminals to receive the second signals from said second decoder matrix; a storage means for each row input terminal and column input terminal; a gate means for each storage means to energize the associated storage means upon the simultaneous occurrence of a first signal and a second signal from the associated row and column input terminals to produce said resulting signal representative of the digit being scanned; and readout means to receive the outputs of said gate means upon the occurrence of said readout signal and thereby record the presence of the digits being read.
 4. The apparatus as claimed in claim 3 in which said scanning means and imaging means are cycled so that the inks are scanned during intervals in which the ultraviolet light is on, so that the inks present will be detected by their fluorescence and in which said illuminating means also includes a source of visible light for periodically illuminating said scanning zone; said array including a light-responsive member which is responsive to visible light, said data being located on an item adapted to reflect visible light, said scanning means being adapted to scan said item during the interval in which it is illuminated with visible light at said scanning zone and thereby energize the associated light-responsive member to enable said readout means; said readout signal being produced when said item leaves said scanning zone; and said storage means including Capacitor means.
 5. In combination, coded data, and a reading apparatus therefor; each datum of said data comprising: a first portion containing a plurality of binarily weighted ink components whose presence or absence defines the significant value of a digit; and a second portion containing a plurality of binarily weighted ink components whose presence or absence defines the particular order of the digit; each said ink component emitting a different specific light frequency when irradiated by ultraviolet light; said apparatus comprising: ultraviolet illumination means for periodically illuminating with ultraviolet light a scanning zone which said data passes; scanning means for scanning a small portion of each datum at said scanning zone; an array of light-responsive means having members, with each one thereof being responsive to only one light frequency emitted from said coded inks so as to indicate the presence or absence of the corresponding ink, thereby defining said datum; imaging means for imaging the light emitted from said inks to each of said light-responsive members of said array, with each of said members which is energized producing a corresponding signal; a first decoder matrix to decode said signals into a first signal representative of the significant value of the datum being scanned; a second decoder matrix to decode said signals into a second signal representative of the particular order of the datum being scanned; and a memory matrix comprising: row input terminals to receive said first signals and column input terminals to receive said second signals; a storage means for each row input terminal and column input terminal; a gate means for each storage means to energize the associated storage means upon the simultaneous occurrence of a first signal and a second signal from the associated row and column input terminals; and readout means for each said storage means to receive the output from the associated storage means upon the occurrence of a readout signal and thereby record the presence of the data scanned. 